This A/SCOR, which is beginning its tenth year of funding, will continue to employ a multidisciplinary approach to elucidate factors involved in the pathogenesis of atherosclerosis. Studies will be carried out in the areas of lipid biochemistry and enzymology, diet-induced primate atherogenesis, hemodynamics, platelet-endothelial interactions, endothelial injury and repair, plasma clotting factors, prostaglandins, lysosomal enzymes, human leukocytes and the atherogenic risk factors in a pediatric population. One of the unique features of this program is the strong emphasis on thrombosis as it relates to the progression and complications of atherogenesis. In this regard, cultured umbilical vein, arterial and brain capillary endothelium are available on a continuing basis for biochemical, immunologic and morphologic study. A major goal is to relate lipid risk factors to thromboatherogenic mechanisms. Another asset is the availability of nonhuman primates in which to investigate the progression and regression of atherosclerosis. A third unique feature is the availability of a large, well-characterized pediatric population for epidemiologic and genetic studies. Our program consists of nine research projects and six supporting core laboratories and facilities. The projects deal with the cellular and membrane aspects of fatty acid saturation; lipid, permeability and morphologic changes in the arterial wall of the primate; hemodynamic changes during progression and regression of atherosclerosis; the role of prostacyclin in endothelial function; the role of antihemophilic globulin and antithrombin III in thromboatherogenesis; the properties of cerebrovascular endothelium; the regulation of fatty acid and sterol synthesis in human monocytes; the recognition, uptake and function of lysosomal acid lipase; and finally, the incidence, prevalence and tracking of hyperlipidemia, hypertension and obesity in a school age population, with emphasis on the familial aspects of lipoprotein and henodynamic abnormalities.